6.9.1.5.3 Basic Query Execution
You can execute PGQL queries using the opg4py.pgql
Python
wrapper.
Executing PGQL Queries Using the Python Client
- Set the graph for querying as
shown:
>>> pgql_conn.set_graph("<graph_name>")
where <graph_name> is the name of the graph.
- Define and execute the PGQL
SELECT
query. For example,>>> pgql = "SELECT e.from_acct_id, e.to_acct_id, e.amount FROM MATCH (n:accounts) -[e:transfers]-> (m:accounts) on bank_graph limit 10"
- Execute and print the result set as
shown:
>>> pgql_result_set = pgql_statement.execute_query(pgql) >>> pgql_result_set.print() +------------------------------------+ | FROM_ACCT_ID | TO_ACCT_ID | AMOUNT | +------------------------------------+ | 781.0 | 712.0 | 1000.0 | | 190.0 | 555.0 | 1000.0 | | 191.0 | 329.0 | 1000.0 | | 198.0 | 57.0 | 1000.0 | | 220.0 | 441.0 | 1000.0 | | 251.0 | 387.0 | 1000.0 | | 254.0 | 188.0 | 1000.0 | | 259.0 | 305.0 | 1000.0 | | 261.0 | 145.0 | 1000.0 | | 263.0 | 40.0 | 1000.0 | +------------------------------------+ PgqlResultSet(java_pgql_result_set: oracle.pg.rdbms.pgql.PgqlResultSet, # of results: 0)
Also, you can convert the PGQL result set obtained in the preceding code
to a Pandas dataframe using the to_pandas()
method.
Note:
Thepandas
package must be installed in your system to
successfully execute the call to to_pandas()
. This package is
automatically installed at the time of the Python client installation. However, if
your call to to_pandas()
fails, verify if the
pandas
module is installed in your system. In case the module
is found missing, then install the pandas
package manually.
Parent topic: Using the Python Client to Execute PGQL Queries